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<head>
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	<meta name="viewport" content="width=device-width, initial-scale=1.0">
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	<title>Document</title>
</head>
<style>
	html,body{
		width: 100%;
		height: 100%;
		margin: 0;
		padding: 0;
	}
		.text{
			width: 100%;
			height: 100%;
		}
		</style>
		<body>
			<div class="text"></div>
		</body>
<script>
	window.parent.subject.subscribe('demo', function(res){
		let text = document.getElementsByClassName('text')[0];
		let li = document.createElement('li');
		li.innerText = res;
		text.appendChild(li);
	})
</script>

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